Police said the boy, William McQuain, of Germantown, remains missing. An Amber Alert was issued for him on Thursday morning.

Officers found the boy's mother, 51-year-old Jane McQuain, dead in her Briarcliff Terrace home Wednesday night. Investigators said there was trauma to her body, and they consider her death a homicide, but they declined to elaborate pending an autopsy.

Police spokeswoman Rebecca Innocenti said an SUV owned by Jane McQuain was found about 8:30 a.m. Thursday in the Charlotte, N.C., area. About an hour later, William's stepfather, Curtis Lopez, was taken into custody there and charged with first-degree murder.

Authorities said William was last seen at his mother's Germantown home on Sept. 30. Investigators said they were hopeful that they'd find the boy with Lopez, but he was nowhere to be found.

"They were like two peas in a pod," one of the boy's neighbors said of him and his mother. "You see mother, you see son. Every time she'd go somewhere, he'd go somewhere."

William is a sixth-grader at Martin Luther King Jr. Middle School. According to a district spokesman, the school calls home when a child is absent, and guidance counselors get involved after four consecutive absences.

It's unclear if the school followed that protocol in William's case. He hadn't been at school for almost two weeks, officials said.

According to the Amber Alert website, the boy is 5 feet tall, about 85 pounds with brown hair and brown eyes.

Anyone with information on the whereabouts of William is urged to call police at 301-279-8000.